This invention relates to recording and/or playback apparatus and, more particularly, to apparatus for indicating the location of particular information which is recorded on the record medium used in such recording and/or playback apparatus.
In the use of recording/playback devices for dictation purposes, an operator often desires to indicate the location of various instructions along the record medium. Typical of such instructions are inserts, deletions, the end of a selected piece of dictation, and the like. In some dictation apparatus, such indications are provided by physically marking the record medium, as by an ink or crayon mark, by a perforation, etc. These indications apprise a transcriptionist of the locations of such special instructions and are helpful in organizing and carrying out the transcription of recorded information.
It has been found that the physical marking of the record medium is not a fully satisfactory method of indicating the location of instructions. Accordingly, the prior art has developed improved indicating mechanisms which scribe marks on an indicating slip usually incorporated into the dictation apparatus. Typically, the slip is an index scale graduated in minutes and marked by, for example, a pencil or the like, by the operator. In many dictation devices, automatic marking devices also have been incorporated into the apparatus. Accordingly, the operator merely need actuate suitable controls on the apparatus to effect a corresponding mark on the index scale.
Although the marked index scale provides a generally adequate indication to a transcriptionist of the relative location of instructions on the record medium, there is the possibility that the marked index scale will be lost or otherwise separated from the record medium. This means that the transcriptionist cannot be apprised of such instructions at the outset of a transcribing operation, thereby contributing to possible confusion, erroneous transcription of dictated information or inordinate delay in completing the transcription.
In an attempt to overcome this problem attending separate, marked index scales, it has been proposed to record predetermined instruction signals on the record medium, these predetermined signals performing substantially the same function as the markings on the index scale. For example, the predetermined instruction signals can be recorded as tone signals which are not audibly sensed during playback. In preparation of a transcribing operation, the record medium is rapidly scanned to detect the presence of these tone signals and to mark an index strip which is scanned in synchronism with the scanning of the record medium when each such signal is detected. One example of such an instruction indicator apparatus is described in U.S. Pat. No. 3,040,135. Various types of marking mechanisms and index strips can be used, and one system proposes a thermosensitive index scale.
Although the technique of recording instruction signals substantially avoids the problem of lost index slips, it is necessary to provide a fresh index slip for each change in the record medium. For example, if the record medium is a magnetic belt, the scanning of that belt will mark one index slip, and the next belt which is transcribed requires the preparation of another index slip. Similarly, if the record medium is magnetic tape, such as a tape cassette, each new cassette requires the preparation of an associated index slip. Hence, index slips must be kept in ready supply.